Toy boats produced by injection moulding, e.g. from PVC, are known. The manufacturing method and the requirement for a nonexpensive product dictate that the design of the product must be subjected to the blow moulding technique, i.e. the blow moulded object can have no parts projecting laterally to the opening direction of the mould. This means that such hollow bodies, even when regarded as toys, in certain cases can only with difficulty be identified for what they represent, particularly when it is a more complex configuration, which is often the case with boats, such as complete fishing boats, tugboats, passenger boats, etcetera. The possibility which has hitherto been available is to use moulds having one or more loose or displaceable cores, which after the blow moulding, is pulled out to allow the blow moulded body to be removed from the mould. Such a mould however is considerably more expensive to obtain, which means that also the product will be more expensive. The blow moulded object furthermore will have the same colour through-out its entire surface so that if it is desired that certain details have other colours, is it necessary for the object to be subjected to a painting procedure.